1. Field of Invention
In the field of medicine lumens are frequently used for a variety of purposes, including but not necessarily limited to for the purpose of transferring liquids and/or gases through and between various medical equipment and/or to and from the patient. In many instances it is highly desirable that these lumens be cleaned and sterilized for reuse. The invention disclosed herein relates to apparatus and method for cleaning said lumens. With additional particularity the invention herein disclosed relates to apparatus and method for creating a pulsating flow of liquid, typically distilled, sterile water through the lumen of said line, followed by flowing a drying gas, typically sterile filtered air, through said lumen to remove most of said cleaning liquid, prior to sterilization and reuse of said lines.
2. Description of Related Art
Historically medical lumens (of medical lines or instruments) have been cleaned prior to sterilization stream, by flushing them with a syringe containing water. Doing so entails a number of issues, including the cleanliness and sterility of the water used, cleanliness of the syringe used, how large the syringe is, how many times the syringe is used, etc. The process of cleaning medical lumen with syringe is a labor intensive exercise, requiring a fair amount of skill. Each time fluid is pushed through the lumen, the lumen must be disconnected from the syringe, the syringe recharged with fluid, the lumen reconnected to the syringe and another charge of fluid pushed through the lumen. It is generally considered advisable to flush the lumen at least four times in this manner. In as much as that is time consuming and takes a fair amount of skill, it is sometimes not done sufficiently, if at all.
Even if a syringe is used to flush the lumen with liquid there remains the question of removing the liquid prior to sterilization. It has been recognized that if liquid remains in a lumen during attempted sterilization that it may create chambers of air in the lumen which are not adequately sterilized by, for instance, steam. Consequently when a syringe is used to flush a lumen with liquid there remains issues with removing at least sufficient amount of the flushing liquid so that air pockets are not formed in the lumen which prevent adequate sterilization thereof. Sometimes a syringe is used in attempt to push air through the lumen, but that entails a number of issues, including but not limited to size of syringe, number of times it is actually used, whether used properly and quality of air (or other gas) used in the syringe. Attempt may be made to drain the lumen, sometimes by aid of centrifugal force (“slinging” the lumen) to encourage liquid to leave the lumen. This poses its own set of issues, including but not limited to sometimes breaking expensive medical equipment. Sometimes air or other gas (such as oxygen) from a pressurized source may be used. That raises several issues, including whether the gas is oil free, and the expense and fire danger associated with use of pressurized oxygen. Despite all of the problems associated with use of syringes to clean lumens they are still widely used, and used improperly, accounting for increase in rate of complications, such as Toxic Anterior Segment Syndrome (“TASS”), in patients following cataract surgery.
Previous art makes some effort to teach devices other than the traditional, problematic method of using syringes to clean medical lumens prior to sterilization thereof. One such device is seen in U.S. Pat. No. 6,206,014 to Cameron et al. Cameron teaches a counter-top instrument which in sequence automatically delivers liquid then air through a medical line. In order to accomplish said function Cameron utilizes a pressure containing bottle and cap and an electrically driven air-pump. In order to charge the device with fluid the pressure containing cap must be removed from the bottle, water or other liquid poured into the bottle (partially filling it) and the pressure containing cap replace. The air-pump is then used to charge the bottle with pressurized air. Two lines draw from the pressurized bottle. One line draws from the bottom of the bottle and is used to dispense liquid. One line draws from the top of the bottle and is used to dispense air. Each line goes to respective valve (each of which is separately operated by electric signal). After the valves the lines are then connected together and to a lumen to be cleaned. Electric timer is provided to activate the air-pump (to build and maintain desired air pressure in the bottle) and to open and close each valve in proper sequence to dispense liquid through the lumen, then dispense air, then close stop both. The Cameron device poses a number of issues. No easy means is provided to filter (or if filtered, to change the filter when clogged, the air it uses. Each time its bottle is opened to refill it with fluid sterility of the system can be compromised. Some may consider use of pressurized bottle and removable pressure retaining cap to present a safety issue. Alternatively, use of low air pressures limits rate of liquid and air flow through lumens to be cleaned. Cameron does not create a pulsed flow of (high and low velocity) liquid which is believed to be superior cleaning lumens. Use of electric timer, having pre-set times not easily variable reduces flexibility of the device. Lack of foot control requires use of at least one hand to activate the device (or in the event of leakage stop the device) which could be better used to control the lines and instruments being cleaned.
The invention herein disclosed and claimed addresses some of these issues.